Newton's Colour Disc, 200mm, hand spun

This apparatus was inspired by the work of Sir Isaac Newton (1642-1727) in showing that white light is made from a range of colours called the spectrum. It consists of a circular disc of plastic with narrow wedges of colours in the hues of the rainbow, plus white. The sequence of colours is repeated four times around the disc. If spun at high speed, the colours on the disc will appear to merge into a off-white tinge due to the persistence of human vision.

The 200 mm diameter disc is mounted on an axle on a wooden handle. It is spun up by means of a pull-cord, rather like a toy gyroscope.